It is a common mistake to assume that an old machine has already been paid: the cost of maintenance tends to grow with time, while the value of the machine drops. There's usually a very definite point after which it is not worth maintaining an old machine, but usually by that time you have spent more money in unnecessary maintenance than you would have spent in upgrading the system when it was the right time.
The same cost exists for software, although because of it's virtual nature, the cost of maintenance grows more because of obsolescence or lack of support, rather than repairs or replacement parts.
Modern apps (the new name of metro) use WinRT, which is NOT a complete CLI environment. It has a subset of the CLR classes, and then adds some proprietary extensions to it. It's designed to ease the walled garden lock-in, not to improve the programming experience.
You can still hear, though. Sound waves can travel through your nose and mouth, and through your bones. In that room there's no sound, at all. Anything you hear will come from inside your own body.
I wouldn't last more than a minute there, though. I become anxious within a few minutes of wearing earplugs, and I need them to swim underwater.